Like radio and optical observations of AGN/Galaxy pairs (e.g. Carilli, C & van Gorkom, J. 1992, ApJ, 399, 373), X-ray observations of the pairs can reveal absorption at high energy band, and also, possible galactic gaseous X-ray emissions that are very useful in constructing halo models. ROSAT/PSPC X-ray spectra of 4 AGNs in the well-known pairs 3C232/NGC 3067, 3C275.1/NGC 4651, 3C309.1/NGC 5832 and Mrk474/NGC 5682 are reported here. Especially, we have detected an extragalactic HI of NGC 5862 in the Mrk474 spectrum.